Characteristics of granulators classified by pelletizing system

Cold pelletizing system granulator:
Flake granulator: After the flakes are produced, the pelletizing operation is carried out. This method helps to detect and screen the quality of the flakes, and it is easier to find the defective parts in the material in the flake state. However, its processing flow is relatively long and there are many factors to consider. For example, when the flakes are pelletized in the subsequent process, the uniform thickness and flatness must be ensured to ensure the uniform quality of the pellets after pelletizing. Moreover, if the size of the pellets needs to be adjusted, the equipment adjustment is relatively complicated.

Strip granulator: Its production line has a low cost, which is a major advantage. The operation is relatively simple and it is very convenient to clean. It is especially suitable for processing needs that require frequent replacement of colorants because it can easily and thoroughly clean the equipment. However, the cooling section will take up a certain amount of space because its length needs to be determined according to the temperature requirements of the polymer. Under large-scale production, this space occupation may become a constraint on the production layout, but if the output demand is not extremely large, it is a more economical granulation option.

Die-face hot pelletizing system pelletizer: This pelletizer pelletizes the material when it is just extruded from the die in a molten state, and then cools it downstream. This method can effectively avoid the problems of uneven stretching and breakage of strips generated in some pelletizing processes, because it pelletizes when the material state is most stable. It can also be customized according to different downstream cooling methods, such as docking different cooling modules such as air cooling or water cooling, so as to flexibly adjust the cooling effect after pelletizing. However, in order to ensure the accuracy and consistency of hot pelletizing on the die surface, the maintenance of the equipment and the high quality of the pelletizing tool are crucial. If the tool wears quickly or the pelletizing is uneven, it will greatly affect the quality of the pellets and the efficiency of the production line.
Underwater pelletizer: Due to the participation of water flow, the water flow can cool and quickly take away the pellets during the pelletizing process of the underwater pelletizer. Therefore, it has great advantages in processing some polymers that are sensitive to temperature or require rapid cooling.

The pelletizer is cooled and flushed by the water flow when pelletizing the molten polymer underwater, which can ensure the service life of the pelletizer. In addition, the presence of water during the whole process makes the pelletizing environment relatively stable, which helps to control the uniformity of the pellets. However, the equipment cost of the underwater pelletizer is relatively high, and it requires supporting water filtration and circulation devices to ensure the cleanliness of the water, thereby ensuring the long-term stable operation of the equipment and the quality of the pellets. If the water filtration and circulation system fails, it is easy to cause abnormal operation of the equipment and deterioration of the pellet quality.